The present invention relates to a circulating fluidized bed apparatus, and belongs to the technical fields such as circulating fluidized beds, chemical engineering and food and pharmaceutical processing.
Since high-humidity high-viscosity materials are difficult to disperse, the materials will be attached to a machine part to be the difficulty in the drying industry. A high-viscosity quick drying machine in the Chinese patent CN2011104233878 of Shijiazhuang NSTL Engineering Technology Co., Ltd. mainly comprises a driving motor, a mainframe, flying teeth, crushing teeth and a turbofan and the like; the high-viscosity quick drying machine is a cylinder, the outer wall is provided with a heating outer sleeve and is subject to heat preservation through a heat insulation material, a flying tooth device makes the high-humidity high-viscosity material continuously dispersed into particles so as to increase heat transfer area, thus it is guaranteed that the materials are not attached to device components, and the high-humidity high-viscosity materials are dried. Mineral grinding is an important production process in cement production; the powder grinding operation in cement production generally refers to grinding the material by a mill and then separating fine powder through a powder selecting machine. Similar power grinding operations are widely used for industries such as metallurgy, chemical engineering and building materials. Due to the fact that fine powder cannot be separated timely through an existing mineral grinding process, the efficiency of the mill is lowered to some extent, and energy consumption is increased; the powder grinding and powder selection operations are finished in different devices, the process flow is long, and the equipment cost is high.
At present, a method for drying and powder grinding of medicine and food materials generally comprises the steps of first drying the materials and then grinding the materials, and the method has the problems of high operation temperature, long operation duration, high loss of effective ingredients, pollution in the production process, etc.; and methods and devices of performing evaporation and distillation, concentration, mixing, screening and sterilization operations and the like have the shortcomings that the energy consumption is high, the adaptability is not wide enough, and the product quality is not good enough.
A molecular sieve dryer is a device which utilizes molecular sieves as adsorbents to dehydrate gas. Molecular sieves of different types have selectivity in absorbing different gases, and by utilizing the characteristics, the molecular sieve dryer is also used for separating specific ingredients out of gas. FIG. 7 illustrates an embodiment of the molecular sieve dryer and the molecular sieve dryer comprises a first molecular sieve container 95, a second molecular sieve container 96, an inlet air pipe 97, a regeneration branch 98 and an outlet air pipe 99. A port of a tee on the inlet air pipe 97 is an air inlet 107 of the molecular sieve dryer, and a port of a tee on the outlet air pipe 99 is an air outlet 120 of the molecular sieve dryer. Molecular sieves and heating devices are installed in the molecular sieve containers. When the first molecular sieve container 95 is in a working state, the molecular sieve in the first molecular sieve container 95 adsorbs moisture and/or specific ingredients in gas so as to dry the gas and/or separate the specific ingredients; meanwhile, the heating device in the second molecular sieve container is started; a vacuum pump on the regeneration branch 98 vacuumizes the second molecular sieve container 96, so that the molecular sieve in the second molecular sieve container 96 is regenerated, and the adsorbed moisture and/or the specific ingredients are adsorbed; when the molecular sieve in the first molecular sieve container 95 is saturated, the second molecular sieve container works instead, and the molecular sieve in the first molecular sieve container is regenerated. A gas treatment apparatus made of molecular sieves has already been widely applied to drying of medium and high pressure gas, separation of specific ingredients and enrichment operation of the specific ingredients. However, the gas treatment apparatus is seldom applied to low pressure gas such as 5000-2000 Pa low pressure gas generated by a fan and seldom used for providing a low moisture and low oxygen content operating medium in drying operations.
An ejector is a device which utilizes a nozzle to spray high-pressure fluid into a mixing pipe, so as to form negative pressure around the nozzle and suck materials through the negative pressure to mix the high-pressure fluid and the sucked materials. When the high-pressure fluid is gas, the ejector can also be used for dispersing liquid and powdered materials into a fluidized state and conveying the materials. FIG. 15 illustrates an embodiment of the ejector, and among markers in the figure, there is a nozzle 270, a vacuum chamber 271, a mixing pipe 272, a diffusing pipe 273, a mixture outlet 274, a nozzle outlet 275, a suction inlet 276 and a high-pressure fluid inlet 277.
A fan is a gas conveying device. Materials are certainly smashed under the an impact effect of fan impellers while the fluidized materials pass through the fan to be conveyed, and under the conditions that the structural strength of the fan meets the requirements, an unexpected remarkable effect can be achieved by using the fan to convey and smash the fluidized materials. However, due to the regulations of most of fan manuals on limitation of dust content in gas conveyed by fans, it leads to the prejudice that the fan cannot be used for directly conveying the fluidized materials, and there are few methods of conveying the fluidized materials through the inside of the fan and methods of smashing through fans.
Apparatuses for powdered material drying, screening and sterilization are disclosed in Chinese patents ZL2010101628876, ZL2011001629417 and ZL2010101628984 respectively. The three inventions are improved based on a fluidized drying machine, are complex in structure and cannot work reliably due to poor circulation. However, the concept of a circulating fluidized bed elaborated in the present inventions is of great significance. The conventional circulating fluidized bed mostly refers to a combustion technology applied to a coal burning boiler, and the three Chinese patents expands the concept of the circulating fluidized bed. The circulating fluidized bed is improved in the Chinese patent 2013107484627, the circulation problem of low-viscosity powdered materials is solved, and the characteristics that the circulating fluidized bed is low in energy consumption, can perform large-scale normal temperature drying quickly and is high in efficiency are highlighted. However, due to the problems that viscous materials are attached to a material-gas separator bag, large mineral materials damage the fan and no economically feasible method is available to provide inlet air stream conforming to the process requirements, the circulating fluidized bed cannot be used for processing high-humidity high-viscosity materials and grinding large mineral materials, the problems occurring in drying, smashing, evaporation and distillation operations and the like cannot be solved, and the requirements of reducing production costs in all industries and improving product quality cannot be met.